I wasn't trying to be pessimistic, just trying not the fall for the "too good to be true" hype machine common in tech (e.g. new batteries with 100x the capacity are right around the corner, carbon nanotubes uses, etc...).

Is this a new idea, though? It's not like supersonic commercial jets are a new thing and they haven't been built. The economics of building a commercially viable production supersonic plane is much more difficult to do than building a car or writing a new website to disrupt Facebook or Google.

I 100% agree that people need to be exploring this stuff. That being said, I'll believe it when I see it.